Kenyan police believe the gang were "preparing to raid the country's communication systems" and that they possessed equipment capable of infiltrating bank accounts, Kenya's M-Pesa mobile banking system and ATM machines, according to the Daily Nation newspaper.

"The suspects are being interrogated to establish their mission in the country and what they wanted to do with the communication gadgets," confirmed the director of Kenya's Criminal Investigation Department, Ndegwa Muhoro.

"They have been charged in court," he added.

A detective close to the case said the raids were sparked after police began investigating a house fire that left one person dead. The source said the charges levelled against the 77 so far include "being in the country illegally and operating radio equipment" without the necessary permits.

According to the Standard newspaper, the Chinese nationals were living in "military-style dormitories", and that China's ambassador to Kenya has also been summoned to "explain if his government was aware of the group's activities".